A supply device of this type is adapted to feed shredded tobacco to the tobacco band. In the process of feeding, the shredded tobacco is air-classified (winnowed) according to weight, to remove heavy tobacco shreds (midribs of tobacco leaves) from a shredded tobacco supply path. As a result, only the tobacco shreds of desired sizes are supplied to the tobacco band.
The shredded tobacco thus subjected to the winnowing can be satisfactorily attracted to the tobacco band by suction, and accordingly, subsequent processes, such as the transfer of the shredded tobacco from the tobacco band onto a wrapper web and the wrapping of the shredded tobacco in the wrapper web, namely, the formation of a tobacco rod, can be stably carried out.
Thus, the process of winnowing shredded tobacco is indispensable for the cigarette manufacturing machine. The following explains the winnowing process in detail.
First, in the process of feeding shredded tobacco, air jets emitted from primary and secondary separators are sequentially blown against the shredded tobacco. The air jets serve to classify the tobacco shreds according to their weights, so that only the tobacco shreds whose weights fall within a predetermined range are introduced into a fluid bed trough. Subsequently, the shredded tobacco is conveyed along the fluid bed trough by air jets emitted from multiple stages of accelerators up to the tobacco band, where the shredded tobacco is attracted to the tobacco band by suction.
The air jets emitted from the primary and secondary separators are used only for winnowing the shredded tobacco and do not substantially contribute to the conveyance of the shredded tobacco along the fluid bed trough. Thus, in order to convey the shredded tobacco introduced into the fluid bed trough up to the tobacco band without fail, it is necessary to use the aforementioned multiple stages of accelerators, namely, the air jets emitted from these accelerators.
In this manner, the shredded tobacco supply device requires not only the primary and secondary separators but also the multiple stages of accelerators and thus consumes much energy, entailing an increased environmental load.
An object of the present invention is therefore to provide a shredded tobacco supply device which permits the air jets from accelerators to be weakened or permits the accelerators to be omitted, thereby effectively reducing the consumption of energy.